Development and function of bombesin-like peptides and their receptors
Published: 1 May 2005
Hiroko Ohki-Hamazaki*,1, Maiko Iwabuchi1 and Fumihiko Maekawa1,2
1Laboratory of Molecular Neuroscience, School of Biomedical Science and Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8519 and 2 Department of Physiology, Division of Integrative Physiology, Jichi Medical School, Kawachi, Tochigi 329-0498, Japan
Amphibian bombesin and its related peptides consist a family of neuropeptides in many vertebrate species. Bombesin and two major bombesin-like peptide in mammals, gastrin-releasing peptide (GRP) and neuromedin B (NMB), have been shown to elicit various physiological effects. These include inhibition of feeding, smooth muscle contraction, exocrine and endocrine secretions, thermoregulation, blood pressure and sucrose regulations and cell growth. Receptors for GRP and NMB (GRP-R and NMB-R), as well as third subtype of bombesin-like peptide receptor (BRS-3) have been cloned. These receptors are G-protein-coupled receptors and are expressed in various brain regions and in the digestive tract. In this paper, we will summarize studies on these peptides and their receptors, with special reference to research using gene-knockout mice. These studies clearly demonstrated the role of three receptors in vivo and in vitro. We will also discuss the phylogeny of these receptors.